Method and apparatus for scanning surfaces

ABSTRACT

A method and apparatus for photo-electrically scanning surfaces having a registration mark thereon capable of reflecting light signals. Means are provided for mounting the object having the surface to be scanned, and suitable drive means are provided for controlling movement of the surface. The area of the surface to be scanned containing the registration mark is bathed with light emanating from a light source such as a fluorescent lamp excited by a filtered direct current supply. A scanner amplifier picks up the reflected light from the registration mark and uses the resulting signal to control the motion of the surface being scanned.

FIPS/ZIZ Ortli 1 51 *Dec. 4, 1973 METHOD AND APPARATUS FOR 3,283,89811/1966 Calhoun 356/240 SCANNING SURFACES 3,478,221 11/1969Sainsbury.... 356/240 3,415,370 12/1968 Husome 356/240 Inventor: WIllIamOrtheb, p 3,439,178 4/1969 Rottman 250/223 13 Hoboken, NJ. 2,863,35512/1958 bedingham 356/240 [73] Assigneez colgawpalmofive Company New3,105,152 9 1963 Nash 250 217 York, NY.

Primary ExammerJames W. Lawrence Notice: The portion of the term of thisAssistant ExaminerD. C. Nelms patent subsequent to Oct. 13, 1980,Attorney-Herbert S. Sylvester, Murray M. Grill, Norhas been disclaimed.man Blumenkopf, Ronald S. Cornell, Robert A. Bur- 1 Filed: Jan. 1971roughs, Thomas .1. Corum, Richard N. Mlller and Rob- Appl. No.: 106,586

Related U.S. Application Data ert L. Stone 57 ABSTRACT A method andapparatus for photoelectrically scanning surfaces having a registrationmark thereon capable of reflecting light signals. Means are provided formounting the object having the surface to be scanned, and suitable drivemeans are provided for controlling movement of the surface. The area ofthe surface to be scanned containing the registration mark is bathedwith light emanating from a light source such as a fluorescent lampexcited by a filtered direct current supply. A scanner amplifier picksup the reflected light from the registration mark and uses the resultingsignal to control the motion of the surface being scanned.

4 Claims, 3 Drawing Figures 1 SCANNER/AMPLIFIER 24 27 .2 2 CLAIREX ceu.I6

26 I2 FLUORESCENT many SOURCE FIG. 2

32 49 N 102 1 93 /I H* 97 9s V ,was 100 95 I 1 I 1 '-4l- 53" 94 PATENTED3.777. 151

465i F/G. g 47 SCANNER/AMPLIFIER 25* CLAIREX CELL I6 FLUORESCENT LIGHTSOURCE I,\'\'H.\'T()H. WILLIAM L. ORTLIEB ATTORNEY 1 METHOD ANDAPPARATUS FOR SCANNING SURFACES This application is a continuation of mycopending application Ser. No. 685,543, filed on Nov. 24, 1967 and nowabandoned.

This application has subject matter in common with application Ser. No.685,458, filed Nov. 24, 1967 now U.S. Pat. No. 3,522,432.

The present invention relates generally to an apparatus for use inconnection with the packaging and handling of various types of articles,and more particularly to a method and apparatus for accomplishingregistration of work pieces by scanning the surfaces thereof forregistration marks placed thereon.

Various types of apparatus and various methods have been used in thepast for aligning containers after labels, logos or the like have beenprinted thereon. Exact alignment with a great degree of accuracy anduniformity is necessary for a branded well known commodity.

With the development of high speed machinery for mass production andpackaging of articles for consumer use, new problems have arisen in thathigh speed scanning must be accomplished with a minimum of rejectsoccurring due to noise" or other problems arising from the scanningsystem itself. The use of illuminating sources operating on alternatingcurrent with fast photo cells has produced noise signals due to lightvariations at a multiple of the line frequency which cannot be filteredout without also filtering the desired signal because the desiredsignals are in the same frequency range.

The present invention has for an object the use of a filtered directcurrent supply on the scanning light source thereby eliminating lightfrequency variations in the light intensity.

A further object of the present invention resides in the direct use of alight source such as that emanating from a fluorescent tube excited by afiltered direct current instead of the light source optically amplifiedto obtain a high intensity spot on the scanned surface. The

direct use of a strong diffused light source such as a fluorescent tubethereby provides relatively high intensity diffused illumination of thescanned area without the disadvantage of optical amplification in thatthe scanned surface motion normal to the scanner is amplifled bychanging the desired focal plane. The use of the relatively highintensity diffused source such as a fluorescent tube provides acomparable light level to a small focused incandescent lamp making anincrease in amplifier sensitivity unnecessary and there is virtually noincrease in bulk and heat dissipation for the same effective diffusedlight level.

Yet another object of this invention resides in the provision of ascanning system employing direct use of a photocell with a lightdirecting tube and without necessity of optical amplification of thereflected light signal, which is desirable to take full advantage of thedirectly used light source.

The apparatus that is utilized in connection with the invention includesa fluorescent tube type light operated on filtered direct current andarranged to bathe the scanned surface and registration mark withdiffused light of non-varying or slowly varying intensity. A scannerusing a photo-conductive cell or photo-voltaic cell sensitive in thereflected wave length region aimed at the bathed area is provided forreceiving light signals from passage of the registration mark as thescanned surface is moved. The registration mark will reflect lightchanges from the passage of the registration mark in a manner as to besensed by the scanner. The signal from the photo-cell of the scanner isused to control the movement of the work piece and hence of the scannedsurface via a self-contained amplifier and associated electro-mechanicaldevices.

The method carried out by the present invention comprises the steps ofapplying a registration mark to a work piece. Then, the work piece ismoved so that the registration mark will pass within the field beingsensed by the scanner. The scanning apparatus will receive light changesfrom the passage of the registration mark through the scanned area. Thescanned area is bathed by light emanating from a fluorescent tubesupplied by filtered direct current. The signal from the scanner is usedto control further movement of the work piece.

It is a further object of the present invention to provide means foralignment of the work piece such as containers including tubes or thelike, which registration marks are readable by automatic scanningequipment to provide for exact alignment of the container for furtherprocessing.

A further object of the invention resides in the provision of anapparatus and method of scanning registration marks on work pieces thatis insensitive to relatively large variations in distance from thescanning apparatus to the work piece so as to permit for axial movementof the registration mark relative to the scanning system during thescanning operations, which was heretofore impractical with focusedscanning apparatus.

A further object of the invention resides in the provision of a novelpower supply arrangement for a light source used in a scanning systemfor eliminating power line frequency variations in the light intensityfor a scanning system.

Still further objects and features of this invention reside in theprovision of an apparatus and method of scanning registration marks thatis simple in construction, adaptable for various use such as in theprinting, packaging, labeling, filling, closing, cutting and shaping ofgoods, which is substantially fool proof in operation and capable ofadaptation to various existing machines and products now in use.

These, together with the various ancillary objects and features of theinvention, which will become apparent as the following descriptionproceeds, are attained by this method and apparatus of scanningregistration marks, a preferred embodiment of the apparatus and systemutilized in the invention being disclosed in the accompanying drawing,by way of example only, wherein:

FIG. 1 is a diagramatic illustration of an embodiment of the scanningsystem according to the present invention;

FIG. 2 is a schematic wiring diagram illustrating one form of circuitrycapable of being employed in the present invention; and,

FIG. 3 is a schematic wiring diagram of the light source and powersupply therefor.

Referring now specifically to the drawing, and more particularly to FIG.1 thereof, there is seen a mechanical arrangement according to thepresent invention. In particular a tube of metal, clear or opaqueplastic, or the like is held at its base in a clamp-like holder 14.

This tube holder 14 is of the type which is itself stationary during theregistration cycle and frictionally grasps the tube 12 with apredetermined light pressure to stop rotation of the tube therein afterrelease of the tube rotating means to be hereinafter defined.

' A registration mark 16 of a color contrasting with the color adjacentto it, is applied in the form of an ink, paint or lacquer on the tube12.

A rotatable spindle l8 equipped with an expanding collet 22 is adaptedto be placed into the neck of the tube 12 to facilitate rotation of thetube 12 through rotation of the spindle 18 by suitable drive means.

A scanner/amplifier assembly 24, including a non-. focused receiverusing a photo-conductive cell 25, such as a Clairex 905HL cell, ispositioned adjacent to the upper part of the tube 12. The receiverincludes a light directing tube 27 aimed at the area to be scanned, toreceive light signals from passage of the registration mark 16 acrossthe scanned area.

A fluorescent tube type light source 26 operating on filtered directcurrent is placed at right angles to the tube 12 and spindle l8 and isadapted to bathe the scanned area with diffused light of non-varyingintensity for one or a plurality of assemblies 24 placed in closeproximity to the light source 26, and other tubes and mechanisms.

Refer now to FIG. 3, the filtered direct current supply is achieved byplacing a bridge rectifier 90, across the alternating current line. Theresistor 91 is a surge limiting means for protecting the rectifier 90,and capacitor 92 serves to filter the rectified D.C. This substantiallyfilters out all of the power supply ripple for the fluorescent lamp tobe hereinafter further described.

After a tube has been placed into the tube holder 14 and the rotatingspindle 18 has been placed in the neck thereof the .tube 12 is rotatedby expanding the collet 22 which grips the inside of the tube 12 untilthe registration mark 16 is positioned directly in front of thescanner/amplifier assembly 24 and the rotation of the tube is stopped bythe signal from the photo-cell 25 caused by the photo-cell beingactuated by reflected light from the registration mark 16.

Referring now specifically to FIG. 2, there is seen a latching amplifierof solid state circuitry wherein the assembly 24 is connected across aD.C. power source 94 at connector terminals 1 and 6. The pulse selectswitch 93 connects a voltage divider formed by the photo-cell 25 andresistor 32 across the power source to form a signal. Signal polaritymay be changed by the switch to provide an amplifier output from eithera light increase or light decrease pulse when the cell 25 receives thelight reflected from the registration mark on the scanned surface. Thisparticular application uses an A.C. amplifier to avoid the effects ofslowly varying ambient light levels and a signal as referred to above isa light change or pulse such as will be obtained from the The voltagechange from the photocell divider circuit will be amplified throughtransistors 49, 50, 96, and 97 and used to energize relay through themachine reset switch 53 at terminal 5. The circuit will electronicallylatch via positive feedback through the switch 53 to transistor 96. Thereset switch 53 serves to deenergize the relay 95 and the solenoid 46,47 by breaking the feedback loop at the end of the cycle.

Resistor 98, capacitor 99 and choke 100 serve to filter electrical noisewhich might be picked up by the latch line where it runs outside theshielded amplifier/- scanner housing. Capacitor 101 and resistor 102serve as a high frequency filter to limit the response of the amplifierat undesired frequencies.

The type of amplifier above described serves to provide the scanningcapability for the circuit and to latch the circuit when theregistration mark 16 on the tube 12 comes in front of thescanner/amplifier 24 actuating solenoid valve 47 thereby stoppingrotation of the tube 12 and holding the tube 12 in alignment for thefilling and closing thereupon.

Other circuitry of either solid state construction or tube amplificationwith latching features could be employed in accordance with the conceptsof this invention.

Referring again in particular to FIG. 3 there is seen a schematic viewof the fluorescent light source 20 including a ballast 70 of the typeG.E. 580690 which is connected in series to a resistor 72 of the valueof 700 ohms/100 watts which in turn is connected in series to one leg ofa fluorescent lamp 26 of the type F6T5CW and to a starting switch 76 forclosing the lamp starting circuit.

From the foregoing description it will be apparent that there isprovided means for detecting registration marks on plastic, metal tubesor the like utilizing a scanner/amplifier assembly and a fluorescentlight to provide for positive registry of tubes after printing and- /orlabeling and prior to filling and closing. The above described deviceprovides for accuracy and sensitivity in response to direct use of D.C.powered fluorescent light which was heretofore unknown when compared tooptically amplified A.C. powered light and therefore provides a meansfor attaining uniformity in a degree never before available with respectto alignment of plastic, or metal tubes and the like without thenecessity of using extra high sensitivity amplifiers and/or extremeprecision in controlling transverse movement of the scanned surface withrespect to the scanner axis.

Although there is shown and described a preferred embodiment of thepresent invention, it is to be understood that various changes andmodifications may be made in the present invention.

1 claim:

1. Apparatus comprising a tube having a registration mark thereoncapable of reflecting light in a photoelectrically discernible visibleportion of the light spectrum, drive means including a rotating spindle,means connecting said spindle and said tube for rotating said tube inaccordance with rotation of said spindle, actuating means forcontrolling the movement and position of said tube, means for bathing atleast the portion of said tube having said mark thereon with diffusedlight of non-varying intensity from a tubular fluorescent light sourceexcited by a flitered direct current supply so that said registrationmark reflects light in said photoelectrically discernible portion of thelight spectrum,

direction at right angles to the tube having a registration markthereon.

3. Apparatus according to claim 1, wherein said filtered direct currentsupply comprises a bridge rectifier, a surge limiting means forprotecting said rectifier, and a capacitor for filtering the rectifieddirect current.

4. Apparatus according to claim 3, wherein said surge limiting meanscomprises a resistor through which rectified current passes and saidfiltering capacitor is connected across the leads which carry therectified, surge limited current.

i It I! t

1. Apparatus comprising a tube having a registration mark thereon capable of reflecting light in a photo-electrically discernible visible portion of the light spectrum, drive means including a rotating spindle, means connecting said spindle and said tube for rotating said tube in accordance with rotation of said spindle, actuating means for controlling the movement and position of said tube, means for bathing at least the portion of said tube having said mark thereon with diffused light of nonvarying intensity from a tubular fluorescent light source excited by a flitered direct current supply so that said registration mark reflects light in said photo-electrically discernible portion of the light spectrum, with said filtered direct current supply eliminating line frequency radiations in the light intensity, scanning means for signalling the presence of reflected light from the said registration mark, said scanning means including a light directing tube, and amplifier means connected to said scanning means for amplifying the signal from said scanning means, said amplifier means being connected to said actuating means for control thereof so that the signal from said scanning means controls the position of said tube.
 2. Apparatus according to claim 1 wherein said tubular fluorescent light source extends longitudinally in a direction at right angles to the tube having a registration mark thereon.
 3. Apparatus according to claim 1, wherEin said filtered direct current supply comprises a bridge rectifier, a surge limiting means for protecting said rectifier, and a capacitor for filtering the rectified direct current.
 4. Apparatus according to claim 3, wherein said surge limiting means comprises a resistor through which rectified current passes and said filtering capacitor is connected across the leads which carry the rectified, surge limited current. 